Which type of bond forms when electrons are transferred from a metal atom to a nonmetal atom?
Ionic bond
Nonpolar covalent bond
Metallic bond
Hydrogen bond
Tap an answer to check it.
WhyIonic bonds form by electron transfer from a metal (forming a cation) to a nonmetal (forming an anion), with the resulting ions held together by electrostatic attraction.
2Multiple choice · Easy
Which of the following best describes a metallic bond?
A lattice of metal cations in a sea of delocalized electrons
Electrons transferred completely from one atom to another
A shared pair of electrons localized between two atoms
Attraction between temporary dipoles in nonpolar molecules
Tap an answer to check it.
WhyIn metals, valence electrons are delocalized into a 'sea' of electrons shared among a lattice of cations, which accounts for conductivity and malleability.
3Multiple choice · Easy
How many valence electrons must be shown in the Lewis structure of CO2?
16
12
10
20
Tap an answer to check it.
WhyCarbon contributes 4 and each oxygen contributes 6, giving 4 + 2(6) = 16 total valence electrons.
4Multiple choice · Easy
According to VSEPR theory, what is the molecular geometry of a molecule with four bonding pairs and no lone pairs on the central atom, such as CH4?
Tetrahedral
Trigonal planar
Bent
Linear
Tap an answer to check it.
WhyFour bonding regions and no lone pairs arrange to minimize repulsion in a tetrahedral geometry with bond angles of about 109.5 degrees.
5Multiple choice · Easy
An alloy is best described as which of the following?
A mixture of a metal with one or more other elements
A pure crystalline ionic compound
A molecular compound of two nonmetals
A network covalent solid such as diamond
Tap an answer to check it.
WhyAn alloy is a mixture of a metal with one or more other elements (often other metals), combining metallic properties; it is a mixture, not a compound.
6Fill in the blank · Easy
A covalent bond in which the bonding electrons are shared unequally because of a difference in electronegativity is called a covalent bond.
Answer:
polar
WhyUnequal sharing of electrons between atoms of different electronegativity produces a polar covalent bond with partial charges.
7Multiple choice · Medium
In a potential energy versus internuclear distance curve for a diatomic molecule, what does the distance at the minimum of the curve represent?
The equilibrium bond length
The distance at which the atoms repel most strongly
The point of zero attractive force
The distance at which the bond dissociation energy is zero
Tap an answer to check it.
WhyThe minimum of the curve corresponds to the most stable arrangement, where attractive and repulsive forces balance; this distance is the equilibrium bond length.
8Multiple choice · Medium
Which molecule is correctly described as having a trigonal pyramidal molecular geometry?
NH3
BF3
CO2
CH4
Tap an answer to check it.
WhyNH3 has three bonding pairs and one lone pair on nitrogen (tetrahedral electron geometry), giving a trigonal pyramidal molecular shape.
9Multiple choice · Medium
What is the hybridization of the central carbon atom in the carbonate ion, CO3 2-?
sp2
sp3
sp
sp3d
Tap an answer to check it.
WhyCarbonate has three regions of electron density (three sigma bonds, no lone pairs) around carbon, corresponding to sp2 hybridization and trigonal planar geometry.
10Multiple choice · Medium
Why does the ozone molecule, O3, require two resonance structures rather than a single Lewis structure?
The actual bonding is a delocalized average that no single structure can show
Oxygen cannot obey the octet rule in any single structure
The molecule contains an odd number of electrons
One oxygen atom always carries a full negative charge
Tap an answer to check it.
WhyExperimentally the two O-O bonds in ozone are identical (intermediate between single and double), so resonance structures are averaged to represent delocalized bonding.
Ready to test yourself?
Practise Molecular and Ionic Compound Structure and Properties with instant marking and per-unit score tracking.